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arXiv · astro-ph/9703147

A spectral study of gamma-ray emitting AGN

M. Pohl·R. C. Hartman·B. B. Jones·P. Sreekumar
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Abstract

In this paper we present a statistical analysis of the gamma-ray spectra of flat-spectrum radio quasars (FSRQ) compared to those of BL Lacs. The average spectra and possible systematic deviations from power-law behaviour are investigated by summing up the intensity and the power-law fit statistic for both classes of objects. We also compare the time-averaged spectrum to that at the time of gamma-ray outbursts. The spectrum of the average AGN is softer than that of the extragalactic gamma-ray background. It may be that BL Lacs, which on average have a harder spectrum than FSRQs, make up the bulk of the extragalactic background. We also find apparent cut-offs at both low and high energies in the spectra of FSRQs at the time of gamma-ray outbursts. While the cut-off at high energies may have something to do with opacity, the cut-off at low energies may be taken as indication that the gamma-ray emission of FSRQs is not a one component spectrum.

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M. Pohl, R. C. Hartman, B. B. Jones, P. Sreekumar. 1997-03-24. A spectral study of gamma-ray emitting AGN. https://doi.org/10.1063/1.53948

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